Two Marines boarded a quick shuttle flight out of Dallas, headed for Houston.
One sat in the window seat, the other sat in the middle seat.
Just before take-off, an Army soldier got on and took the aisle seat next to the two Marines.
The Soldier kicked off his shoes, wiggled his toes and was settling in when the Marine in the window seat said, "I think I'll get up and get a coke."
"No problem," said the Soldier, "I'll get it for you."
While he was gone, the Marine picked up the Soldier's shoe and spit in it. When the Soldier returned with the coke, the Marine in the middle seat said, "That looks good, I think I'll have one too."
Again, the Soldier obligingly went to fetch it and while he was gone, the Marine picked up the soldier's other shoe and spit in it. The Soldier returned and they all sat back and enjoyed the rest of the short flight to Houston.
As the plane was landing, the Soldier slipped his feet into his shoes and knew immediately what had happened.
"How long must this go on?" the Soldier asked.
"This fighting between our services? This hatred? This animosity?
This spitting in shoes and peeing in cokes?"